Selling an S9, buyer wants SN to check if still in warranty Safe to give out SN?

[GeefeeDollarSign]

First time reseller of Antminer S9's

Buyer wants me to give him the serial number so he can check if it is still under warrenty. Is it ok to give out a SN?

S9 is brand new in box but i opened top flap of box.

[GeefeeDollarSign]

apologies if im in the wrong section. New here.